Roofing sheet



Feb. 1940- A. B. HASWELL ROOFING SHEET 3 Sheets-Sheet 1 Filed May 27,1935 INVENTOR. ARTHUR .45. fiqswt-LL.

m i 'flww w w" ATTORNEYS A. B. HASWELL ROOFING SHEET Filed May 27, 19353 Sheets-Sheet 3 INVENTOR.

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ATTORNEYS Patented Feb. 20, 1940.

UNITED STATES PATENT OFFICE 3 Claims.

One of. the chief features of the invention resides in the provision ofa sheet having a major portion of its area substantially fiat, but withits lower end transversely cambered thus providing a concavo-convexportion arranged in such manof my improved sheet is preferably providedwith one or more transverse ribs which insure maintaining the camberduring shipment and also provide a desirable stifiness in the lower endof the sheet, which maintains the integrity of the structure in theassembled roof. The above and further .detailed features of theinvention will be fully apparent from the follow-- ing specification,drawings and claims.

In the drawings- Fig. 1 is a vertical section through a portion of aroof illustrating the improved roofing sheet of the present invention;Fig. 2 is a plan viewpf one of the sheets embodying the invention; Fig.3 is a typical cross section through the fiat portion of the sheet, thesection being taken, for example, at the plane indicated by 3-3 of Fig.2; Fig. 4 is a cross section through the cambered portion of the sheet,the section being taken on line 4-4 of Fig. 2; Fig. 5 is an enlargeddetail section on line 55 of Fig. 2; Fig. 6 is a similar enlarged detailsection taken on line 66 of Fig. 2 and showing the overlapping of theridge portions of two adjacent sections; Fig. 7 is an enlarged sectionon line 'l'I of Fig. 2; Fig. 8 is a plan view of a portion of. acompleted roof employing sheets of thepresent invention; Fig. 9 is asection on line 99 through the joint where the sheets overlap; Fig. 10is a section on line l0l0 intermediate the points where upper and lowersheets overlap; Fig. 11 is a plan view illustrating a modification.Referring in detail to the drawings, the roofing sheet of my inventionhas a major portion which is substantially flat. The range of the fiatsection extends from the upper edge of the sheet, indicated at IUapproximately to a line indicated 50 at l2. Throughout the major area ofthe sheet, therefore, the same is substantially flat, its cross sectionhaving the appearance shown in Fig. 3. The fiat surface is broken onlyat the sides and center by the usual form of raised ridges, which 55 aresubstantially V-shape. In the sheet illustrated, there are a pair ofparallel ridges l4 and l6, l8 and 20,'at the sides of the sheet and anintermediate ridge22 at the'cente'r of the sheet. In some cases,however, there may be a greater orlesser number of these ridges and, ifdesired, 5 the central ridge may be entirely omitted. A particularfeature of the invention resides in providing the sheet with lowerportions which are cambered with the crowns of the cambered portionsbeing lowermost. In the sheet illustrated, as' best shown in Fig. 4, thecambered portions are indicated at 24 and 26 and provide concaveconvexfaces, the convexfaces being on the un- .derside of the sheet, asclearly shown. These cambered portions occupy the limited zone at thelower end of. the sheet beyond the line indicated at l2 in Fig. 2. Andthe lower end of the sheet, as best shown in'Fig. '7 is inclined down-:wardly, the angle of inclination being indicated bJy the dotted linesa: and y. The line a: corresponds to the surface line of the roof onwhich the sheets are to be laid, which line of course is coincident withthe underside of the flat portion of thesheet.

Extending transversely of the cambered portion of the sheet, Ipreferably provide cambered 'stifiening ribs, such as indicated at 28.These ribs are unsymmetrical. That is to say, each rib comprises arelatively wide portion 30 and a narrow shoulder portion 32, theshoulder portion of. 30 one rib merging into the wide portion 30 of thelower rib. These ribs are also cambered to follow the curvature of thelower cambered portion of the sheet. Preferably, they are relativelyshallow, as compared with the depth of the ridges l4, l6,

- l8and 22 and may merge thereinto, as shown for example in Figs. 5 and6. Or, as shown in Fig. 11, the shallow transverse ribs may terminateshort of the V-ridge as at 3|.

The sheets are adapted to be laid up in such a way that the camberedlower end of one sheet overlaps the flat upper end of an underlyingsheet.

Figs. 8 to 10 inclusive illustrate a portion of roof employing thesheets of the present invention and illustrate the manner in which thesheets are laid up. For convenience in these figures only, we haveidentified the separate sheets by numerals I, 2, 3 and 4, illustrating atypical sequence of installing the roofing. In these figures, sheet i isfirst laid and then followed by sheets 2, 3 and 4. The lead lines andarrow heads in Fig. 8 show the respective edges of the four separatesheets. Reading this drawing in connection with the sequence in Figs. 9and 10 makes it clear, for example, that at the point where upper sheetsoverlap lower sheets, for example, as indicated by the section taken online 9-9 (Fig. 8) there is two-ply metal between the outer V-ridges andfour-ply metal at the edges.

At points intermediate the ends of the sheet, as indicated by Fig. 10,taken on line III-I of Fig. 8, it is clear that there is a single-ply ofmetal at the body portion of the sheet and twoply metal at the edgejoint where the ridges overlap. In applying roofing of this type, thenails are usually placed about twelve inches apart and are driventhrough the apex of the V-ridge next to the top edge of the sheet, asillustrated.

The invention is directed primarily, though not exclusively to the usualtin or other metallic sheets. Roofing sheets of this general characterheretofore used have been open to the objection that the metal beingthin has a tendency to buckle or warp. This is a common defect in sheetsheretofore used. And although ribs have been resorted to in some casesthis does not solve the problem. But the utilization of a camberedsheet, as above .described, provides for deliberately employing adefinitely shaped warpage which will be taken up when the sheet isnailed in contact with the fiat portion of an underlying sheet.

By providing the crowned or cambered sheet with the transverselyextending reinforcing rib, the integrity of. the crowning is maintainedduring shipment. And by slightly inclining the lowermost extremity ofthe crowned part of the sheet, it will be appreciated that when the sameis nailed down a close fit will be made with the underlying sheet. Thiswill prevent any substantial quantity of water being driven upwardly. Itwill also prevent the tendency of loosening the sheets by wind pressure.The transverse ribs 28 will also provide grooves or air spaces. And, asis well known in the art, such ribbing has a tendency to preventobjectionable capillary action.

Various modifications may be made by those skilled in the art withoutdeparting from the invention as defined in the appended claims.

What I claim is:

1. A metallic roofing sheet, the major area of which is flat and whoselower end is transversely cambered to provide concave-convex faces, theconvex face being on the underside of the sheet,

said cambered portion being adapted to overlap the fiat portion of asimilar sheet and to be flexed transversely to make a snug fittherewith.

2. A metallic roofing sheet having respective parallel ridges extendinglengthwise along each edge and along the intermediate portion ofv thesheet, the major area of the sheet being fiat, and respective endportions thereof on opposite sides of the intermediate ridge beingtransversely cambered to provide respective concavo-convex faces, saidconvex faces being on the underside of the sheet, said cambered portionsbeing adapted to be flexed transversely to make a snug fit with the fiatportion of a similar sheet.

3. The roofing sheet of claim 1 further characterized by the provisionof transverse ribs in the cambered portion adapted to insure maintainingthe camber during handling and shipment of the sheets.

ARTHUR B. HASWELL.

